# Monthly Archives: August 2013

## Counting Nearby Stars

In my previous post, I casually stated that there are 61 stars in the region within 5 parsecs of the Sun -- at least according to the Gliese Catalog of Nearby Stars. I did not state where you could get … Continue reading

Posted in Astronomy | Comments Off on Counting Nearby Stars

## Radio Communication Between the Stars

Introduction A phone call from a cancer epidemiologist a few months ago got me thinking radio communication over long distance. This researcher was a sharp guy who immediately saw the dynamic range issues associated with cell tower communication -- the … Continue reading

Posted in Astronomy, General Mathematics | 7 Comments

## Battleship Rangefinders and Geometry

Quote of the Day Russia is a riddle wrapped in a mystery inside an enigma. — Winston Churchill. Introduction While reading a web page on WW2 naval warfare, I found some interesting material on how naval gunfire was spotted -- … Continue reading

Posted in Naval History, optics | 19 Comments

## Distance to the Horizon Assuming Refraction

While doing some reading on lighthouses, I needed a formula to compute the distance to the horizon as a function of height. This formula would give me an idea of how far away a lighthouse could be seen. Continue reading